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CAS 1 record

CAS 155633-54-8

CAS 155633-54-8 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 155633-54-8
CAS 155633-54-8PubChem CID 9848888

Drometrizole trisiloxane

Drometrizole trisiloxane is a photostable UVA and UVB light filter. The compound is a lipophilic benzotriazole derivative marketed as Meroxyl XL by L'Oreal, although sunscreens with drometrizole trisiloxane are currently only approved for use in the EU, Canada, Australia, and Japan, among other countries. Despite being used elsewhere in the world with relatively few reports of adverse reactions, the FDA continues to cite that the existing scientific record is not sufficient to establish the compound as being generally recognized as safe and effective for over-the-counter sunscreen use. — DrugBank

IUPAC name
2-(benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-[methyl-bis(trimethylsilyloxy)silyl]propyl]phenol
Molecular formula
C24H39N3O3Si3
Molecular weight
501.8 g/mol
Exact mass
501.22992172 Da
Topological polar surface area
69.4 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
5
Covalent units
1
Defined stereocentres
0

Also known as

SilatrizoleMexoryl XLOR 10154OR-101542-(2H-1,2,3-benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-(2,2,4,6,6-pentamethyl-3,5-dioxa-2,4,6-trisilaheptan-4-yl)propyl]phenolPhenol, 2-(2H-benzotriazol-2-yl)-4-methyl-6-(2-methyl-3-(1,3,3,3-tetramethyl-1-((trimethylsilyl)oxy)-1-disiloxanyl)propyl)-Phenol, 2-(2H-benzotriazol-2-yl)-4-methyl-6-(2-methyl-3-(1,3,3,3-tetramethyl-1-((trimethylsilyl)oxy)disiloxanyl)propyl)-Phenol, 2-(2H-benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-[1,3,3,3-tetramethyl-1-[(trimethylsilyl)oxy]-1-disiloxanyl]propyl]-
16 more reported names
2-(2H-1,2,3-benzotriazol-2-yl)-4-methyl-6-(2-methyl-3-(2,2,4,6,6-pentamethyl-3,5-dioxa-2,4,6-trisilaheptan-4-yl)propyl)phenolRefChem:135828919-634-2Drometrizole trisiloxane [WHO-DD]2-(2H-Benzo[d][1,2,3]triazol-2-yl)-6-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)-2-methylpropyl)-4-methylphenolUNII-HC22845I1XDrometrizole trisiloxane [INCI]2-(2H-Benzo[d][1,2,3]triazol-2-yl)-6-[3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)-2-methylpropyl]-4-methylphenolEBC-27246HY-W419643DROMETRIZOLE TRISILOXANE [USP-RS]2-(2h-benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-[1,3,3,3-tetramethyl-1-[(trimethylsilyl)oxy]disiloxanyl]propyl]phenolTS-10004DB-091411CS-0539357Drometrizole trisiloxane, analytical standard
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 155633-54-8

1 total
Annex
VI
Entry
16

DROMETRIZOLE TRISILOXANE

Phenol, 2-(2H-Benzotriazol-2-yl)-4-Methyl-6-(2-Methyl-3-(1,3,3,3-Tetramethyl-1-(Trimethylsilyl)Oxy)-Disiloxanyl)Propyl
EC
—
Max concentration

How CAS 155633-54-8 is used on this site

CAS 155633-54-8 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 155633-54-8 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 155633-54-8 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

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